Drying apparatus



F. C. STEPHENS.

DRYING APPARATUS.

v v APPLICATION FILED MAY 14,1918. 1,408,483. I Patented Mar. 7,1922

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F. C. STEPHENS.

DRYING APPARATUS.

APPLICATION FILED MAY 14. I918.

1 ,4Q8,4-.83. Patented Mar. 7, 1922.

. 3 SHEETS-SHEET 2.

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F. C. STEPHENS.

DRYING APPARATUS.

APPHCATION FILED MAYH; 1918.

1,408,483. Patented M r. 7, 1922.

3 SHEETS-SHEET 3.

UNITED STATES PATENT OFFICE.

FLOYD C. STEPHENS, OF BUFFALO, NEW YORK, ASSIGNOR TO THE WITTEMANN COMPANY, OF BUFFALO, NEW YORK.

DRYING APPARATUS.

Specification of Letters Patent. Patented Mar, 7, 192-2.

. Application filed May 14, 1918. Serial No. 234,494.

To all whom it may concern..-

' Be it known that I, FLOYD C. STEPHENS, a citizen. of the United States, residing at Buffalo, in the county of Erie and State of New York, have invented a new and useful Improvement in Drying Apparatus, of which the following is a specification.

This invention relates to drying or desiccating apparatus of the kind having a rotary member or members which are coated with the material to be dried and from which the dry powder is scraped.

The objects ofthe invention are to provide an apparatus of this kind in which two co-operating drums are so arranged as to forma part of a receptacle for the material to be dried and in which means of improved construction are employed for forming a water-tight connection between the drums and the walls of the receptacle; also to provide an apparatus of this kind in which the receptacles for the dried material are arranged at the sides of the apparatus; also to provide the drying drums with means of'improved construction for removing condensed Water therefrom; also to provide the fioat' chamber of an apparatus of this kind wlth means forheating the material to ensure the tree flowing thereof; also to improve the construction of apparatus of this kind in other respects hereinafter specified.

In the accompanying drawings:

Fig. -1 is a side elevation, partly broken away, of a drying apparatus embodying the invention. 1 i

Fig. 2 is an end elevation thereof showing the feed end.

Fig. 3 is a transverse section of one of the drying drums showing the means for removing condensed water from the drum.

Fig. 4 is an end elevation of the drying apparatus, partly in. section, showing the other end of the apparatus, on an enlarged scale. I

Fig. 5 is a fragmentary sectional view thereof on line 5-5, Fig. 4, showing the packing for maklng' a substantially watertight connection between the walls of the re ceptacle for the material to be dried'and the drying drums.

Fig. 6 is a fragmentary endelevation of the apparatus showing the means for adjusting the packing means shown in Fig. '5.

suitable construction, that shown 1 The apparatus shown in the drawings'is pr marily intended for drying brewers yeast, which is usually in' a liquid, semiliquid or semi-gelatinous form and which must be heated to a temperature at which the yeast isrendered inactive. In the con struction shown, the drying drums are heated and form a part of the receptacle for the yeast to be dried, thus serving the purpose of heating the yeast in the receptacle and drying the same when it is coated on the drums. It will be understood, however, that the apparatus is not limited to be used in connection with the drying of yeast, but can be used for other purposes. 9

Theframe of the apparatu paratus and are arranged. with their cy1in I drical. surfacesin contact or in such close proximity to eachother as to form the bottom of a container for the material. to be dried. This container isprovided with longitudinal side walls C and with end walls I) 1 which have substantially water-tight connections with the revolving surfacesofthe drums B B. The lower edges of'the side walls C for this purpose are providedwith suitable flexible strips 0 which may. be made of felt or other suitablematerial, and which engage the cylindrical surfaces of the drying drums. c

The end walls D areprovided at their lower edges with packing means. adapted to engage the cylindrical surfaces of the drums and which are adjustable so that the packing may-at all timesbe kept tight. In the construction shown forthis purpose, a substantially V-shap'ed packing-member (Z-is provided which is made in two arc-shaped parts or sections meeting at the apex of the V-shaped member and conforming substan tially with theperipheries of thedrying drums. Each of. the parts of the packing member is provided with a packing strip d of Babbitt or other suitable material which is adapted to be pressed against the periphery of a drum so as to format tainedi tight. 'metal packing is used'in a joint ofthis kind,

the end wall D. After a packing member cl has been adjusted as desired, relatively to the drums B, it is secured in the adjusted position by means of a plurality of screws. or bolts; d which clamp, the packing menu,-

ber against the end walll). As the packing strip d wears out, the-boltscl canbe tight ened so as to take up the wear and in this manner the joints between the encbwalls D and the drums can at alltinies be mainlVhen Babbitt oi-"other "soft a water-tight connection can beiormed between the end walls and the peripheral surface of'the drums and a good bearing surface is also formed between the packing and the drumswhich produces very littleifriction. I

i The drying drums rotate in'the direction indicatedby the arrows in Fig; 4, and the peripheries thereof are coated whilein contact with the material in the receptacle. The material is dried on the surface of the drums while assingfrom the receptacle to scraping mem ers or knives E which,'in the construction shown, are mounted on suitable holders 6 having'arms e engagedby adjusting. screws 6? by means of which the knives can be adjusted relatively to the drums. The adjusting screws c are arranged on' brackets e extending outwardly fromknifesup orting framese secured to the sidewalls The knives E may beof any suitable construction and extend lengthwise throughout the length ofthe drums.

The material scraped from the drumsby the. knives falls upon'inclined plates or "chutes I e" which direct T the driedf material into troughs or conveyer housings F ar- "ranged at opposite sides of the apparatus beyond the sides of the drying drums. The material may be removed from'the troughs F in any suitable manner,"forexample by means of. screw conveyers f arranged inthe troughs, and which move the dried'material tojthe endsof'the troughs where it may be cfollectedby any suitable means, notf'shown. The screw conveyers also serve the purpose of breaking up the dried material if the same is scraped from the rolls inthe form of flakes. The inclined plates or chutes c extend over the edges of a drip pan or receiver f which may be of any suitable' construction and which isarranged below the driving drums so as to receive anywet material which may drop from the drums or which may leak out of the receptacle for the material to be dried. By means of the construction shown, no wet or moist material can become mixed with the dried ma terial.

The receptacle for the material; to be dried is provided with an upper extension or boiling box G which is suitably secured to the walls of the receptacle and forms an, extension thereof. This boiling'box prevents the material from boiling over and when the apparatus is used for'drying yeast, the foam formed during the heating of the yeast is confined in the boiling box. The boiling box is provided with the usual fiu'e'o'r exhaust -pi'pe g-byzmeans of which the steam or vapor is withdrawn fromthe boiling box, and an overflow pipe g is also preferably prov-idedwhich is adapt d to prevent -the overflow of the receptacle and which ter'lninates at its lowerend inthedrip pan f. a The exhaust pip'eg is providedwitha branch 9 'extendingdown into the drip pan f to 'withdraw moisture'therefrom and from the; surfaces ofthe 'drying-dr-ums. f The boiling box is provided lids 9 V The drying drums in the construction shown are heated, by steam which is supplied to the drums by means or a'steam pipe I having branchesleading to each drum, each branch terminating in a pipe fitting H having a. central steam supply pipe it secured thereto in such a-manne-r as to receiive the steam from the pipe 7a, Each of the steam supplypipes h extends through a hollow rotary-trunnion or stud shaft b of the corresponding drying drum and terminates in the interior'of the drunu The pipe h is of smaller diameter than themten nal' diameter of the shaft 7130f the drum so that an annular passage is formed between the rotary shaft and" the fixed steam supply pipe, through which condensed water or steam may. bedischa-rged fromthe drying drum; h represents a gland connecting the stationary pipe fitting. H and the rotary shaft/z"; Apipeh connects with the pipe fitting H to withdraw thecondensed water and to discharge the same to a steam trap ll- Any othermeans fonsuppl'yinm steam to. the drying drums may be provided-i The followingmeans are preferably pro vided for discharging the condensed water from the steam drums into the annular passages in the stud shafts h The stud with usual hinged covers or shaft of each drying drum is provided withan extension or part I having a lateral arm [to which a water scoop K is secureda The scoop K has an outer portion or wall 7:: which is substantially of the same curvature as the periphery of; the'drying drum and is" arranged in close proximity thereto. The scoop hasan opening k facing the direction of rotation of the scoop and] drying drum,

throughwhich the water may enter into the scoop. The scoop is fixed relatively to the drum, so that when the scoop and drum rojtate, thefwater will pass into a pipe 70 connecting the scoop with the part I, causing the water to flow through the hollow shaft if. The fact that the scoop is raised above the levelof the shaft 7L2 increases the head of water therein so as to ensure the discharge of the same to the steam trap. Since the scoop rotates with the drying drum, *there are no contacting surfaces" between the drum and the scoop and the water is substantially continuously removed from the drum.

The drying drums may be driven in any suitable manner, for example by means of worms L suitably mounted on a driving shaft Z and engaging worm gears Z Fig. 1, secured on the stud shafts k of the driving drums. Sprocket wheels Z are mounted on the stud shafts 72. and are connected by means of chains to sprocket gears Z mount ed on the shafts of the conveyors f.

WVhen the apparatus is used in connection with a thick liquid, such for example as yeast, it is desirable to provide means for heating the liquid fed to the apparatus to ensure a continuous flow thereof. In the construction shown, a float chamber or regulating device M is provided for maintaining a substantially constant level of liquid in the receptacle for the material to be dried, and it may be of any desired construction. The float chamber, in the construction shown, is provided with jacketed walls on to which exhaust water or steam is supplied from the steam trap through a pipe m so that the proper operation of the float Cllitlih her is ensured without excesive heating of the material in the float chamber. The water may be discharged from the jacketed walls by means of a discharge pipe m By heating the float chamber, a constant supply of material to the apparatus is assured, as well as the accurate control of the level. of liquid in the apparatus.

The apparatus described has the advantage of being thoroughly reliable in operation and assuring a thoroughly unifornr coating of the drying drums. The arrange ment of the troughs or conveyer housings at the sides of the apparatus positively prevents any moist or wet material from becoming mixed with the dry material, which is particularly important when the apparatus is used for drying yeast, since a small quantity of wet yeast will spoil a large quantity of dry yeast if mixed therewith. The construction of the container for the material to be dried as described ensures a water-tight structure which is essential to the successful operation of the apparatus. The water scoop described quickly removes water from the drying drums and therefore keeps these drums operating at their highest eillciency. By means of the arrangement ofthe steam and condensed water connections described, all the steam and water piping is arranged at one end of the apparatus and the dried material is discharged at the other end. This structure adapts the apparatus particularly well for the arrangement of two of the drying apparatuses endwise with regard to each other, so that all the driedmaterial can be discharged into a single receptacle and also avoids all possibility of iavin'o' moisture from the steam and water connections spoil the dried material.

I claim as my invention:

1. In a drying apparatus, the combination of a pair of drying drums arranged in close proximity to each other and forming a bottom of a receptacle for the material to be dried, side walls and end walls for said receptacle, arc-shaped packing members movably mounted on said end walls and adapted to engage the curved peripheries of said drums, and means for adjusting said packing members toward and from said drums relatively to said end walls.

members relatively to said cylindrical surfaces to make'a tight joint.

3. In a drying apparatus, the combination of a pair of drying drums arranged in close proximity to each other and forming a bottom of a receptacle for the material to be dried, are shaped end walls for said receptacle, metallic packing members movably mounted on said walls and adapted to enthe cylindrical surfaces of said drums, pressure devices arranged on said end walls for engaging said packing members at in-' tervals for adjusting portions of said packing members relatively to said drums, and means for clamping said packing members againstsaid end walls to hold the same in their adjusted positions.

4i. In a drying apparatus, the combination of a pair of drying drums arranged in close proximity to each. other and forming a bottom of a receptacle for the material to be ceptacles, are shaped metallic packing members movably mounted on said end walls and extending circumferentially of said drums, means mounted on said end walls for adjusting said packing members toward and from said dru is, and means for clamping said packing members to said end walls to hold the same in their adjusted positions.

5. In a drying apparatus, the combination of pair of drying drums arranged in close proximity to each other and forming a bottom of a receptacle for the material to be dried, side walls and end walls for said re- 7 said packing members for-,adjusting the same relatively to said; drums. v V

fitness my hand, this, 7th, day f; May,

1918. i t FLOYD? C. v STEPHENS.

' \Vitnesses;

I. RI E, L. M. UEBELE. i 

